Begin by salting a large pot of water and bringing it to a boil—this takes time, so start here. While the water heats, slice the flank steak into thin 1/4-inch pieces and season generously with salt and pepper on both sides. Slice the onion into thin rings, slice the mushrooms about 1/4-inch thick, and mince the garlic fresh. In a small bowl, whisk together the beef broth, Worcestershire sauce, and flour until completely smooth with no lumps—this prevents gravy lumps later. Once the water boils, add the egg noodles and cook according to package directions, stirring occasionally. The noodles will finish around the same time as your stroganoff, which is perfect timing.

Heat a large, heavy-bottomed skillet over medium-high heat and add 2 tablespoons of the butter. Once the butter is foaming and just beginning to brown, add the seasoned flank steak in a single layer—work in batches if needed to avoid overcrowding, which would steam the meat instead of browning it. Sear for about 3 minutes per side until deeply browned and cooked through. I always let the meat develop a good crust before flipping because that’s where the flavor lives. Transfer the cooked steak to a clean plate and set aside.

In the same skillet with the beef drippings, add the remaining 2 tablespoons of butter over medium heat. Add the sliced onions and cook for about 3 minutes, stirring occasionally, until they begin to soften and turn translucent. Add the sliced mushrooms and increase the heat slightly to medium-high; cook for 5-7 minutes, stirring often, until the mushrooms release their moisture and begin to brown—this concentrates their earthy flavor. Stir in the fresh garlic and cook for just 1 minute until fragrant. The mushrooms’ browning and the garlic’s bloom create the aromatic foundation for a deeply flavored stroganoff.

Pour the dry white wine into the skillet and use a wooden spoon to scrape up all the browned bits stuck to the bottom—this is called deglazing, and those browned bits are concentrated flavor. Let the wine reduce for about 3 minutes, stirring occasionally, until it reduces by roughly half and the sharp alcohol flavor cooks off. Slowly pour in the broth-flour mixture from Step 1, stirring constantly to incorporate it smoothly into the pan juices. Continue stirring and let the sauce simmer for about 5 minutes until it thickens enough to coat the back of a spoon—the flour acts as a thickener, creating that classic creamy stroganoff consistency.

Reduce the heat to low to prevent the yogurt from curdling. Stir in the Greek yogurt or sour cream until fully incorporated and creamy. I find that Greek yogurt adds richness and tang without making the sauce feel heavy, which is perfect for feeding a crowd. Add the cooked beef from Step 2 back into the pan and stir gently to combine everything, warming the meat through for about 1-2 minutes. Taste and adjust seasoning with additional salt and pepper as needed.

Drain the cooked noodles from Step 1 and divide them among serving bowls or plates. Ladle the stroganoff sauce with beef and mushroom mixture generously over the noodles. If using fresh parsley, sprinkle it over the top for a pop of color and fresh herbaceous finish. Serve immediately while hot.